In addition to physical health effects, cancer survivors are known to be at increased risk for a variety of long- term psychosocial effects, most commonly depression and anxiety.3, 7-12 Young adult (YA) survivors are a particularly vulnerable group, as cancer disrupts their physical and emotional development, and they will live with late-effects for many years after treatment.12, 15-18 Studies of YA survivors show high rates of psychological distress,10, 19 as well as many barriers to receiving appropriate psychosocial care.12, 20, 21 Research to understand the etiology of these psychological late-effects and to identify and treat affected survivors has benefited from the use of self-report symptom checklists developed for psychiatric populations,12-14 but almost no research has been done to validate these measures in cancer survivors. In fact, reviews of YA survivor care consistently note that both research and patient care are hampered by a lack of patient reported outcome (PRO) measures that have been validated for this population.15, 20, 21 To address this critical need, this study investigates validity of existing measures of anxiety and depression by comparing them to a validated psychiatric assessment in a sample of 200 YA cancer survivors (age 18-40). Using the Structured Clinical Interview for DSM Disorders (SCID) 22 as a gold standard, the validity of the Brief Symptom Inventory-18 (BSI- 18), 23 and PROMIS initiative 24, 25 anxiety and depression short forms will be assessed. Previous research supports reliability of the BSI-18 and PROMIS measures, 13, 24, and 25, 27 but no studies have validated them against a psychiatric diagnostic criterion. In addition to checklist measures, validity and utility of an innovative diagnostic interview, the Primary Care Evaluation of Mental Disorders (PRIME-MD), administered using computerized automated telephone interview (ATI) will also be investigated. Studies have validated both in-person and ATI versions of PRIME-MD in psychiatric and medical patients, 28-31 but this will be the first to study its utility in cance survivors. Analysis will focus on identifying case-rules for study measures to optimize identification of survivors with clinically significant depression and anxiety on the SCID. The study will also assess whether survivors are more comfortable disclosing sensitive information regarding sexual and suicidal symptoms using ATI compared to written forms, with the goal of determining if ATI enhances reporting of these important but often neglected symptoms. By examining the criterion validity of these measures, and identifying best methods for using them to detect survivors with clinically significant psychological symptoms, this study will greatly enhance the value of these measures and provide new approaches for research and clinical care of YA survivors. Although this research takes place in the context of YA cancer survivorship, results will be informative for developing best practices for enhancing PRO measures of psychological distress and sensitive behaviors in other populations. PUBLIC HEALTH RELEVANCE: Young adult cancer survivors experience significant disruptions in their physical and emotional development, leaving them at risk for psychological distress even many years after treatment. Research to uncover the risk factors for these psychological late-effects, and to identify and treat affected survivors has been hampered by a lack of self-report distress measures that have been validated in this population. By identifying the best methods for using self-report measures to detect young adult survivors with clinically significant psychological distress, this study makes an important contribution to research and clinical care of young adult cancer survivors.